apparatus and instruments for optical transmission, namely lasers and light emitting diodes, photo-detectors, optical transmitters, optical receivers, optical generators, optical switches, optical amplifiers, optical modulators, optical couplers, optical cables, optical waveguides; control circuitry; computers; microprocessors; optical data carrier in the form of discs, tapes and cards; encoded computer programs for optical data transmission; and cables for electrical or optical signal transm...